1. Field of Invention
This invention relates to food and, more particularly, to a water and fat or oil stabilizer and a texture improver for use in food which is able to function through a broad temperature range. The stabilizer of the present invention is especially suited for frozen foods and foods made with mechanically separated meats.
2. Prior Art to Invention
Water and fat/oil are present in virtually all foodstuffs and especially all prepared foodstuffs. Typically, prepared foodstuffs go through a broad range of temperatures, freezing (xe2x88x9225xc2x0 C.) to canning or retorting (120xc2x0 C.) to baking (250xc2x0 C.), as well as prolonged storage, oftentimes in either a chilled or frozen state prior to consumption. The broad temperature ranges and extended storage have a deleterious effect on the stability of the water and fat/oil in the foodstuff. Both water and fat/oil tend to migrate out of the foodstuff during prolonged storage and when the foodstuff is heated. This deleterious effect manifests itself in a number of ways, for example the foodstuff becomes dry or soggy, greasy, tough, chewy or brittle. These problems are due not only to simple movement of the fat/oil and water in the foodstuff but also to the breakdown of the foodstuff, such as the breakdown of the oil emulsion. The problem of stabilizing water and fat/oil in a foodstuff is especially a problem in the food industry where the foodstuff is subjected to a myriad of stresses due to the equipment used to mass produce the foodstuff.
To date, no one stabilizer has been found that is able to function in such a broad range of temperatures and to withstand extended frozen storage. There is a need in the food industry for a stabilizer that can withstand commercial processing, prolonged storage and operate in a broad temperature range, xe2x88x9225xc2x0 C. to 250xc2x0 C., without breaking down.
Broad temperature ranges and prolonged storage at cold temperatures can also have a deleterious effect on the texture and mouth feel of a foodstuff. There is a need for a stabilizer which maintains or improves the texture and mouth feel of foodstuffs.
Texture and mouth feel is especially important with mechanically separated meats. Mechanically separated meats, sometimes referred to as fine ground meats or mechanically deboned meats, are a species of ground meat. Mechanically separated meat is meat that is separated from the bone and, in the case of poultry, from the skin, by machine. Because of the reduced cost for mechanical deboning of meat, there has been a recent increase in the use of mechanically separated meats. This is especially true for poultry, such as turkey and chicken.
The texture of mechanically separated meat is mush or a fine ground product, hence the texture of foodstuffs made with mechanically separated meat has been a problem. For example, mechanical deboned poultry is used in sausage products, i.e. meat stuffed in a casing, and especially hot dogs or frankfurters. The amount of mechanically deboned poultry added to a sausage product must be controlled because too much impairs the texture of the product and makes it too mushy. Generally, the amount of mechanically deboned poultry used for sausage products is no greater than 20%.
There is a need for a texture improver which has a positive effect on the texture of mechanically separated meats and which allows for an increase in the amount of mechanically separated meats in sausage.
It has now been discovered that the stabilizer of the present invention improves the texture of mechanically separated meat and broadens their use in foodstuffs.
Furthermore, the stabilizer of the present invention works to stabilize fat or oil and water in food and operates in a broad temperature range, over prolonged storage periods, and under commercial processing conditions. By preventing the loss of water from a foodstuff, microbial growth or spoilage of the foodstuff is also delayed and/or prevented. Also, by stabilizing fat/oil and water, emulsions of fat/oil in water which are present in a number of foodstuffs such as salad dressing are also stabilized.
The stabilizer of the present invention works not only to prevent moisture loss of a stored, frozen or chilled food but also to prevent moisture loss after heating and prior to consumption of that frozen or chilled food. The stabilizer of the present invention also prevents moisture loss from fresh breads and the like which are prepared from either fresh dough or frozen dough, thereby extending the shelf life of the farinaceous product. It has also been found that the stabilizer of the present invention also increases the shelf life of meat products such as summer sausage which does not require refrigeration, as well as improve the texture of foodstuffs made with mechanically separated meats.
In other words, the stabilizer of the present invention works in a broad temperature range and in a variety of foods and does not break down even after being subjected to prolonged periods in the freezer and the stress of cooking in a wide variety of foodstuffs. The stabilizer of the present invention has also been found to withstand repeated freeze-thaw cycles. Furthermore, novel canned meats can be formulated using the process of the present invention from mechanically separated meats.
Foodstuffs which can be stabilized and/or have their texture improved include eggs, ground meats, mechanically separated meats, dough, sauces, gravies, and farinaceous products.
Broadly, the process for stabilizing water and/or improving texture of food such as mechanically separated meats in accordance with the present invention comprises the steps of:
(a) forming a slurry of gelatin, acid and water, at a temperature of about 0xc2x0 C. to about 100xc2x0 C., for a period of time of at least about 10 minutes, to fully hydrate said gelatin, said acid being present in an amount to cause said slurry to have a pH of about 1.0 to about 4.5;
(b) maintaining the pH of said slurry at about 1.0 to about 4.5;
(c) recovering a gelatin component having a pH of about 1.0 to about 4.5 from said slurry; and
(d) adding said gelatin component to a foodstuff and/or said mechanical separated meat having water in an amount sufficient to stabilize said water and/or improve the texture of said foodstuff or meat.
Optionally, the recovered gelatin component is first dried and then added to a foodstuff in a particulate form. In either case, the stabilizer improves the texture of the foodstuff prepared with mechanically separated meat. Also, during the hydration of the gelatin, steps (a) and (b) above, it is best to agitate the slurry to provide a uniform slurry. Alternatively, some of the water is removed and the fully hydrated gelatin in slurry form is employed.
In order to stabilize both water and a fat/oil in foodstuffs as well as improve the texture of mechanically separated meat, it is preferred to incorporate a starch component and/or a sugar component into the foodstuff along with the gelatin component. The starch component and/or sugar component is suitably employed in the present invention either:
(1) by being added to the acid-gelatin slurry during hydration;
(2) by being dried with the gelatin and acid;
(3) by being mixed with the dried particulate gelatin; or
(4) being added to the foodstuff along with the gelatin component.
Suitable starch components include flour, starch granules, pregelatinized starch, chemically modified starch, and derivatives of starch such as dextrins, maltodextrins, and corn syrups. Suitable sugar components include monosaccharides such as glucose, fructose, ribose, arabinose, mannose, xylose or galactose; disaccharides such as sucrose, maltose, cellobiose, lactose, or trehalose; and trisaccharides such as maltotriose, raffinose, cellotriose or manninotriose.
It has been found that the amount of acid can be reduced in the slurry if a sugar component selected from the group consisting of monosaccharides and disaccharides is present. Where the stabilizer of the present invention is used in a farinaceous product, it is preferred that a portion of the acid be reduced in the slurry and a sugar component selected from the group consisting of monosaccharides and disaccharides be substituted for a portion of the acid. Good results have been obtained with sucrose, glucose and fructose.
The amount of gelatin in the slurry is suitably about 0.5% to about 30% by weight and preferably about 1% to about 10% by weight. The amount of gelatin component added to the foodstuff is suitably about 0.1% to about 15% by weight foodstuff and, more preferably, about 0.1% to about 5% by weight foodstuff. It has been found that the higher the Bloom of the gelatin, the lesser the amount of gelatin added to the foodstuff to get the same effect. In other words, a 100 Bloom gelatin needs three times as much gelatin as a 300 Bloom gelatin to accomplish the same effect in accordance with the present invention.
The amount of starch component used in the slurry, step (a), is suitably about 0.5% to about 20% by weight and, more preferably, about 1% to about 10% by weight slurry. The amount of starch component added to the foodstuff, step (c), is about 0.05% to about 10% and, more preferably, about 0.25% to about 5.0% by weight based on the weight of foodstuff. If flour is used as the starch component, more flour is necessary than granular starch or other forms of starch. The amount of sugar component added to the slurry in step (a) is suitably about 2% to about 3%.
In U.S. Pat. No. 4,588,603 issued May 13, 1986, a process for preparing a stabilized food is disclosed wherein the stabilizer is an aqueous solution of fully hydrated, fully-swollen gelatin and an acid. The stabilizer of the ""603 patent requires the use of non-halogenated water. Applicant has found that by using enough acid to lower the pH to about 1.0 to about 4.5 and maintaining the pH to about 1.0 to about 4.5 to recover a gelatin component at a pH of about 1.0 to about 4.5, that tap water can be used in preparing a food stabilizer.
The stabilizer of the present invention stabilizes both water and fat/oil in a variety of food systems to include eggs, dough, sauces and gravies, mechanically separated meats and ground meats. For instance, in a frozen burrito, the stabilizer of the present invention is used both in the filling of the burrito as well as the flour tortilla. In a frozen pancake, the stabilizer of the present invention is used in both the pancake itself as well as the maple syrup which is used on top of the pancake, both of which were frozen and pre-wrapped for sale to the consumer. In yet another example, the stabilizer of the present invention is used not only in the filling of a chicken pot pie but also the crust. Alternatively, the stabilizer is used only in the crust of the pie and not in the filling to stabilize the crust only.
It has been found that tne stabilizer of the present invention not only stabilizes the water and fat/oil in the food but also prevents the food containing the stabilizer of the present invention from absorbing water and fats/oils. Such is beneficial in crusts, coatings, breadings, batters, and dough since it means that where the farinaceous product contains the stabilizer of the present invention while a portion of the foodstuff does not, that portion of the foodstuff that does not contain the stabilizer will not effect the farinaceous portion of the food.
It has also been found that the stabilizer of the present invention will continue to operate in the foodstuff even after the foodstuff has been heated for consumption. Even though the stabilizer of the present invention does not easily break down in the food system, it is digestible by humans and classified as generally recognized as safe (GRAS) for human consumption. Furthermore, a novel canned meat can be prepared using the stabilizer of the present invention.
The gelatin component is prepared through a slow hydration process wherein acid, water and gelatin are held between about 0xc2x0 C. and about 100xc2x0 C. over a period of at least about 10 minutes, more preferably, about xc2xd hour to about 1xc2xd hours, so as to fully swell and hydrate the gelatin. Optionally, the hydrated acidified gelatin can be heated after being hydrated. Preferably, a slow heating process is employed such that the gelatin granules are allowed to hydrate and fully expand under controlled conditions to thereby increase their water and fat/oil stabilizing capability. Such a slow heating process is conducted at temperatures of about 10xc2x0 C. to about 100xc2x0 C.
The water used to form the slurry can contain halogen, e.g. chlorine, bromine and fluorine; and metal ions which are found in conventional tap water; so long as the pH of the slurry is maintained throughout the process.
The amount and type of acid are essential elements in obtaining the stabilizer of the present invention. If the water is too acidic, then the gelatin is case hardened and, unable to fully swell. If the water is not acidic enough, then the gelatin does not fully swell. The pH of the water must be between about 1.0 and about 4.5 and preferably about 4 throughout the hydration phase.
Suitable acids such as glacial acetic acid, citric acid, malic acid, ascorbic acid, succinic acid, tartaric acid, hydrochloric acid, sulfuric acid, phosphoric acid, lactic acid, maleic acid and aqueous solutions thereof can be used. The preferred acids are glacial acetic, citric, hydrochloric, sulfuric, phosphoric and lactic, with phosphoric being most preferred.
The amount of acid is sufficient to adjust the pH to within the desired range of 1.0 to 4.5.
In one specific example which is especially useful for dough-type products with leavening, the gelatin is prepared by using between 6 and 60 parts of water at about 10xc2x0 C. and 25xc2x0 C. combined with enough phosphoric acid to adjust the pH of the water to about 2, and then adding about 1 part of gelatin to form an acidic gelatinous aqueous slurry. The slurry is then mildly agitated for a period of time sufficient to disperse uniformly the gelatinizing agent throughout the solution so as to form a gelatinous slurry. The agitation usually continues for approximately 5 minutes. Next, the slurry is maintained at a temperature of between about 10xc2x0 C. and 25xc2x0 C. until the gelatin granules have become partially swollen and hydrated, usually between 15 and 25 minutes. The slurry is then agitated and heated to a temperature of between about 30xc2x0 C. and 50xc2x0 C. until the gelatin granules become further swollen and hydrated whereby the slurry becomes smooth and non-granular to feel. The slurry is usually held at this temperature for a period of between 10 and 30 minutes. The slurry is then further heated under agitation to a temperature of between about 65xc2x0 C. and 70xc2x0 C. until a uniformly clear solution is obtained. The pH of the slurry is periodically monitored throughout the process and adjusted to about 4 at the end of the process before recovering the gelatin component.
Conventional equipment is used to conduct the soaking and subsequent heating of the slurry. The slurry is mildly agitated throughout the heating program to maintain a uniform dispersion of gelatin and acid in water.
In one embodiment, the slurry is dried in any conventional manner to a moisture content of about 1% to about 15% and, more preferably, about 6%. The drying is done in a conventional way using conventional equipment, e.g. spray dryer, drum dryer, tray dryer, oven dryer, and freeze dryer. Good results have been accomplished with using a spray dryer or tray dryer. For small scale operations, a convection oven has been used with good results. The drying must be gentle enough so as not to destroy the gelatin while still driving off the moisture. The swollen gelatin and acid which is dried in an oven on a tray forms continuous sheets of material. These sheets must be ground so as to make them readily able to be added to food. Depending upon the volatility of the acid used during hydration of the gelatin, some of the acid will be driven off during drying.
Gelatin is a product obtained by the partial hydrolysis of collagen derived usually from the skin, white connective tissue, and bones of animals. It is a derived protein composed of various amino acids linked by adjacent amino and carbonyl groups to provide a peptide bond. Type-B gelatin is prepared by swelling the raw materials (usually ossein or hide stock) in an alkali saturated lime solution for 3-12 weeks. On the other hand, type-A gelatin is prepared by swelling raw materials (usually pork skins) in a dilute acid solution at a pH of 1 to 2 for 10 to 30 hours. The acid solution is prepared from hydrochloric acid, sulfurous acid, phosphoric acid or sulfuric acid. In accordance with the present invention, type-A gelatin or type-B gelatin may be utilized. The gelatin is also classified by Bloom strength. Bloom strength is a conventional numerical designation which distinguishes gelatin on a gel strength basis. Preferably, the Bloom strength of the gelatin employed in the present invention is about 175 to about 300 and, more preferably, about 200. The lower the bloom strength of the gelatin, the larger the amount of gelatin needed. When the gelatin has a Bloom of 275, the preferred amount of gelatin in the foodstuff is 0.25% to 5% by weight foodstuff.
The formation of the stabilizer of the present invention is preferably accomplished by mixing a starch component in with the slurry of acid and water and gelatin in the hydration step. The starch component added during the hydration step is preferably starch granules, pregelatinized starch or lightly modified starch. Preferably, the starch component is selected from cereal grains, tubers or roots, with the cereal grains such as wheat and corn being preferred. Whichever starch component is used, it should be capable of fully gelatinizing. In the case of pregelatinized starch, the starch granule is generally completely gelatinized after the first heating step at 30xc2x0 C. to 50xc2x0 C. In the case of starch granules, it is generally necessary to heat the slurry in the second heating step to about 80xc2x0 C. to about 95xc2x0 C. and hold the slurry at that temperature for about 10 to about 20 minutes to fully gelatinize the starch granules. Naturally, the temperature and time necessary to fully gelatinize the starch granules will be dependent upon the gelatinization point of the starch.
In one specific example, when pregelatinized starch is utilized, the stabilizer is prepared by combining between about 6 and 50 parts of water and enough acid to adjust the pH of the water to about 1.0 to 4.5 and then adding about 1 part of a mixture of gelatin and starch (the gelatin to starch being in a proportion of 1:6 to 1:1) to the water at a temperature of between about 10xc2x0 C. and 25xc2x0 C. to form an acidic gelatinous aqueous solution. The solution is then agitated for a period of time sufficient to thoroughly mix the gelatin and starch throughout the solution so as to form a gelatinous slurry. Agitating the solution for about 5 minutes is usually sufficient for this purpose. The slurry is then maintained at a temperature of between 10xc2x0 C. and 25xc2x0 C. until the gelatin granules have become partially swollen and hydrated. This step is usually conducted for between 15 and 25 minutes. Next, the slurry is heated to a temperature of between about 30xc2x0 C. and 50xc2x0 C. and is maintained at this temperature for about 10 to 30 minutes at which time both the gelatin as well as the pregelatinized starch are fully hydrated and wherein the slurry has been transformed into a uniformly clear solution. The slurry is then raised to a temperature of about 65xc2x0 C. to about 70xc2x0 C., preferably 68xc2x0 C., and can be dried in a conventional manner using conventional equipment as previously described.
In yet another example, the stabilizer is prepared from water, acid and a mixture of gelatin and starch. The stabilizer is formed by combining between about 6 and 50 parts of water, enough acid to adjust the pH of the water to about 1.0 to about 4.5 and then adding about 1 part of a mixture of gelatin and non-gelatinized starch (the gelatin to starch ratio being between 1:6 to 1:1) to the water at a temperature of between about 10xc2x0 C. and 25xc2x0 C. thereby forming an acidic gelatinous aqueous solution. Next, the solution is agitated to disperse uniformly the gelatin and starch throughout the solution thereby forming a gelatinous slurry. The agitation may be continued for about 5 minutes. The slurry is then maintained at about 10xc2x0 C. to about 25xc2x0 C. until the gelatin granules have become partially swollen and hydrated. This hydration step usually takes between 15 to 25 minutes. The slurry is then heated to between about 30xc2x0 C. and 50xc2x0 C. and maintained at this temperature for about 10 to 30 minutes under agitation. At this point, the gelatin granules have become fully hydrated. Next, the slurry is raised to a temperature of between about 80xc2x0 C. and 95xc2x0 C. and maintained at this temperature for between 10 to 20 minutes. The slurry is then dried as described heretofore if desired.
It has also been found that the stabilizer of the present invention can be formed in-situ where the gelatin component is first made and then the starch component and the gelatin component are added and mixed at the same time with the food ingredients.
Where the formation of the stabilizer is in-situ, the food ingredient along with the stabilizer must be heated to above about the gelatinization point of the starch component to gelatinize the starch component.
The stabilizer of the present invention is added to the prepared foodstuff during initial preparation. Broadly, the stabilizer is added to the foodstuff in an amount sufficient to stabilize both the water and/or fat/oil present in the foodstuff and/or improve the texture of the foodstuff. This amount will vary depending on, primarily, the amount of water and/or fat/oil that is present in the foodstuff and the degree of texture improvement necessary.
More specifically, the amount of stabilizer added to the foodstuff will depend on the amount of water and/or fat/oil which is liberated by the foodstuff. Water is often liberated by a foodstuff during storage in a freezer, conventionally referred to as ice crystal formation, on the food and/or packaging. Both water and fat/oil are liberated during cooking, especially in a microwave oven, prior to consumption of the food product.
Preferably, between about 0.1 to about 5.0 parts by weight of the stabilizer of the present invention where the total weight of the food system is 100 parts is used in the foodstuff. Good results have been obtained using about 0.2 to 0.5 parts by weight of the stabilizer of the present invention based on 100 parts by weight of foodstuff.
As noted above, a cased or canned meat as well as ground meat and mechanically separated meat, in general, having improved texture can be made using the stabilizer of the present invention. Broadly, in order to make a cased or canned meat in accordance with the present invention, the following steps are employed:
A) dissolving gelatin in water by first hydrating gelatin in water with a sufficient amount of acid to adjust the pH of the water to about 1 to about 4.5, and then heating the hydrate gelatin to about 140xc2x0 F. (60xc2x0 C.) to fully dissolve the gelatin in the water, optionally, the hydrated gelatin is added to meat and the meat is then cooked to cause the gelatin to fully dissolve;
B) hydrating starch in water, optionally in the presence of sodium tripolyphosphate;
C) combining a ground meat with a sodium salt to form a mixture;
D) mixing the hydrated or dissolved gelatin, the hydrated starch and the meat and salt mixture to form a meat formulation; and
E) optionally casing or canning or further processing said meat formulation to produce a cased or canned meat or other foodstuff having mechanically separated meat with improved texture.
The acidified, hydrated gelatin can be added to the meat directly, or the acidified, hydrated and heated solution of gelatin added to the meat, or the acidified, hydrated and slow heated gelatin added to the meat. Any one of these three stabilizers can be added to the meat.
The amount of sodium tripolyphosphate used in the present invention is suitably about 0.01% to about 2% by weight foodstuff (meat) and preferably about 0.1% to about 0.50% by weight foodstuff.
Suitable ground meat includes chicken, pork, beef, turkey, horse, lamb and fish. Good results have been obtained with chicken. Such ground meat includes mechanically separated meat.
The presence of sodium in the cased or canned meat is important and it is preferred that the amount of the sodium in the formulation is about 0.25% to about 5% by weight of the formulation. Good results have been obtained when the salt content of the meat formulation is about 2% by weight of the formulation. Suitable sodium salts include sodium chloride.
The amount of stabilizer, gelatin-starch-salt, added to the mechanically separated meat to improve its texture is about 0.1% to about 50% by weight meat and, more preferably, about 1% to about 20% by weight meat. Good results have been obtained when the mechanically separated meat has about 5-10% by weight meat.
The canning process is accomplished in a conventional manner using conventional equipment. Typically, the raw ingredients are combined, placed into a container and the container sealed. The sealed container is subjected to high temperatures to commercially sterilize the contents of the container. This process is also conventionally referred to as retort food processing.
The cased meat is made in a conventional manner using conventional equipment. Suitably, after the meat is formulated, it is then stuffed into a casing. The casing is usually either the intestines of an animal such as a sheep which has been fully cleaned or a man-made synthetic casing.
The use of the stabilizer of the present invention allows for mechanically separated meat to be used alone or with conventional ground meat in the cased meat while still providing the texture and mouth feel of a conventional cased meat.
Such cased and canned meats include sausage, bologna, frankfurters, luncheon meats, SPAM(copyright)-like products, salami, ham, chicken loaf, and turkey loaf.
The preferred amount of each component in the cased or canned meat is:
A more preferred formulation for the cased or canned ground meat made in accordance with the present invention is:
All of these percents are based on the total weight of the foodstuff (meat formulation).